The Effect of Cold on the Skin Barrier / 대한피부과학회지

BACKGROUND: Cold is considered an important environmental factor on the skin's barrier function. It is also known that cold can disrupt the barrier's permeability function. Historically irritant contact dermatitis develops frequently amongst fish processing workers. This means that cold may disrupt the skin barrier function. However, there are only a few studies of the effect of cold on the skin barrier. OBJECTIVE: The aim of our study was to investigate the effects of exposure to the cold on the skin's barrier permeability, calcium gradient and cornified enveloped proteins. METHODS: Hairless mice were classified into four groups as follows; tape-stripping and exposure to cold (4degrees C) for 5 hours group (Group 1), exposure to cold (4degrees C) for 5 hours after tape-stripping and occlusion with Gore-Tex group (Group 2), exposure to cold (4degrees C) for 5 hours after tape-stripping and applying with petrolatum group (Group 3), and tape-stripping and exposure at room temperature (25degrees C) for 5 hours group (Group 4). Next, rate of barrier recovery was measured, and skin of cold exposure site was taken for immunohistochemistry of cornified enveloped protein, calcium inon capture chemistry and in situ hybridization. RESULTS: Rate of barrier recovery of Group 1 was measured at -56.33%, the most delayed rate of all groups. Rate of barrier recovery of other groups were measured as follows; Group 2 (20%), Group 3 (55%) and Group 4 (41.78%). In calcium-ion capture cytochemistry, Group 1 appeared to absent calcium deposit in the entire epidermis. Group 3 appeared to the highest density of calcium in entire epidermis. In immunohistochemical staining of cornified enveloped proteins including involucrin, loricrin and filaggrin, Group 1 resulted in the lowest expression of cornified enveloped proteins. Of all groups, Group 3 appeared to have the highest expressionof cornified enveloped proteins. In situ hybridization of loricrin and filaggrin, expression were similar with results of immunohistochemical staining. CONCLUSION: Our results provide that cold impairs the skin's barrier permeability by having a negative effect on recovery of calcium gradient and differentiation of cornifed enveloped proteins. But occlusion with vapor permeable membranes such as Gore-Tex or petrolatum could improve conditions of skin barrier impaired by cold by restoring the recovery rate of calcium gradient and differentiation of cornified enveloped protein.

The Effect of Barrier Recovery using Topical Steroid and Systemic Steroid after Acetone-application in Hairless Mice / 대한피부과학회지

BACKGROUND: Acetone disrupts the cutaneous permeability barrier through the removal of stratum corneum lipids. This pertubation of barrier integrity stimulates a variety of homeostatic repair that ultimately results in the normalization of barrier function. OBJECT: To measure the effect of steroid on the barrier recovery of acetone applied skin. MATERIAL AND METHODS: The flank skin of 8~10 week old hairless mice was treated with acetone and then topical and systemic steroids were applied. Transepidermal water loss(TEWL) was checked after 0, 3, 6, 12 and 24 hours. Electron and light microscopic examination and ion capture cytochemistry were performed after 3, 6, 12 and 24 hours after systemic and topical steroids had been applied. RESULTS: The results were as follows ; 1) During 3~6 hours after experiment, the recovery rate of TEWL was most prominent in the group of acetone applied animal than other groups. 2) After 12 hours after acetone applied, formation of new stratum corneum was found in the groups of acetone applied or acetone applied skin with topical steroid application. But loss of stratum corneum was observed in the groups of high or low dose steroid injection. 3) Ruthenium tetroxide staining of acetone alone or topical steroid treated specimens after 12 hours experiment revealed that the lipid bilayer was partly impaired and fragmented. Intercellular spaces were widening and the lipid bilayer disappeared or was damaged in the groups of high or low dose steroid injection. 4) Six hours after acetone application, pattern of calcium distribution had been partially reestabilished in the group of acetone alone or topical steroid treated animals. But calcium content was still sparse and decreased from the stratum granulosum to basale in the groups of high or low dose steroid injection. CONCLUSION: In summary the present study demonstrates that steroid treatment acutely delays recovery rate of TEWL, inhibits normalization of calcium gradient or epidermal lipid synthesis that leads to abnormalities in permeability barrier homeostasis.

The Iontophoresis Effect on Recovery After Acute Epidemal Barrier Disruption / 대한피부과학회지

BACKGROUND: The stratum corneum(SC) has a permeability barrier function which regulates percutaneous absorption by the inhibition of transepidermal water loss(TEWL). Acute mechanical or chemical disruption of the SC induces the impairment of the permeability barrier and so increases the TEWL. The calciumtion has been recognized as an important ion in the recovery of the skin barrier. Recently the main delivery pathway of iontophoretic drugs have been suggested by SC interstices. However the morphologic changes in the SC interstices and calcium after iontophoresis have not been reported. OBJECTIVE: The aim of our study is to confirm that iontophoresis may induce changes in the SC interstices and delay the recovery of the barrier after disruption. MATERIALS AND METHODS: After tape stripping the hairless mouse flank skin, the iontophoresis power supply (6V, 0.6mA) was connected to the patch atiached for 2.5 hours to the stripped site. We checked the THWL 0, 2.5, 6, 12, 18, 24 hours after the tape stripping and obtained specimens and performed osmium tetroxide, ruthenium tetroxide postfixation and calcium ion-capture cytochemical stains for electron microscopic study. RESULTS: The recovery rate of the TEWL in iontophoresis was lower than in the control. This was especially so in the anouse which had received anode iontophoresis for 6 hours. It showed statistically lower TEWL than in the control(p<0.05). Anode iontophoresis induced low calcium in stratum granulosum (SG), but cathode iontophoresis induced high calcium in SC. After iontophoresis there were changes in the SC interstices structures. CONCLUSION: Iontophoresis can induce changes in the SC interstices and calcium distribution and so may help the topical drug delivery system.